5 Precautions for Testing Printed Circuit Boards
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- Issue Time
- Jul 29,2021
Summary
The printed circuit board needs to be tested after the production is completed to detect whether there is an unreasonable design. This article will specifically introduce five precautions for testing printed circuit boards.
In the link of printed circuit board design and production, the final step is to test it to observe whether there are fault points or unreasonable designs, and then make timely adjustments. In the process of testing, many matters need to be paid attention to to prevent measurement errors. The following are five precautions for testing printed circuit boards.
1. The internal resistance of the test instrument should be large
When measuring the DC voltage of the IC pins, a multimeter with the internal resistance of the meter head greater than 20KΩ/V should be used, otherwise there will be a large measurement error for the voltage of some pins.
2. Pay attention to the heat dissipation of the power integrated circuit
The power integrated circuit should have good heat dissipation, and it is not allowed to work in a high-power state without a heat sink.
3. The lead should be reasonable
If you need to add external components to replace the damaged parts of the integrated circuit, small components should be selected, and the wiring should be reasonable to avoid unnecessary parasitic coupling, especially the grounding between the audio power amplifier integrated circuit and the preamplifier circuit end.
4. To ensure the welding quality
The soldering needs to be firmly soldered, and the accumulation of solder and the pores are likely to cause false soldering. The soldering time is generally no more than 3 seconds, and the power of the soldering iron should be about 25W with internal heating. The integrated circuit that has been soldered should be carefully checked. It is best to use an ohmmeter to measure whether there is a short circuit between the pins, confirm that there is no solder adhesion, and then turn on the power.
5. Don't easily judge the damage of the integrated circuit
Do not judge that the integrated circuit is damaged easily, because most integrated circuits are directly coupled. Once a certain circuit is abnormal, it may cause multiple voltage changes, and these changes are not necessarily caused by the damage of the integrated circuit. In addition, in some cases When the measured voltage of each pin matches or is close to the normal value, it may not always indicate that the integrated circuit is good. Because some soft faults will not cause changes in DC voltage.
The inspection of the printed circuit board is related to the final use performance and work effect, so we need to pay attention to each test step. If you want to learn more about printed circuit boards after reading the above content, please contact us for professional solutions. The PCBs we design are of excellent quality, durable, and can meet your diverse needs.
As a professional PCB product manufacturer, we always insist on providing customers with high-quality and safe products. We have an experienced production team and a strict quality inspection system. Whether it is product design or assembly, we will carry out comprehensive quality control and detailed processing. We will also develop effective solutions and provide thoughtful one-stop services according to customer needs. If you are interested in our printed circuit boards, please contact us immediately!